1. Field of the Invention
The present invention relates to a white light emitting diode (LED) package and to a white LED package that emits white light with an incandescent color.
2. Discussion of the Background
White LED packages using an LED as a white light source instead of a traditional incandescent lamp or a fluorescent lamp have been increasingly developed. An LED package typically uses a semiconductor LED that emits light by recombination of electrons and holes at a p-n junction upon application of an electric current.
A conventional white LED package may be fabricated using trichromatic LED chips that emit red, green, and blue light. However, such an LED package may not produce uniform white light due to differences in distance between the trichromatic LED chips. Further, a white LED package may be developed that produces white light via a combination of a blue LED chip and a yellow phosphor. This conventional LED package has a simple circuit configuration and may be cost effective, but may exhibit low color reproducibility due to low light intensity at long wavelengths.
Numerous studies have been carried out to develop an LED package that emits optimal white light in terms of color uniformity and color reproducibility. An incandescent lamp is well known as a light source which is close to a Plankian radiator. The incandescent lamp emits a warm white light at a temperature of about 2854K based on the CIE1931 standard, which provides a warm and comfortable atmosphere and an enhanced aesthetic appeal of a colored object. For that reason, there is a need in the LED field to develop an LED package emitting white light more similar to the incandescent lamp.